Control techniques in high-speed atomic force microscopy

Biological macromolecules are highly dynamic. Their functions results from dynamic structural changes and dynamic interactions with other molecules. The visualization of the dynamic processes at high spatial and temporal resolution appears to be straightforward to understanding the functional mechanisms of biological macromolecules. Such visualization is only possible by the atomic force microscope (AFM) with a high-speed imaging capability, since dynamic biomolecular processes generally occur on a millisecond timescale. Therefore, we have been improving both the scan speed as well as the tip force exerted on the sample by developing various devises and techniques. The latest version of our high-speed AFM can capture biological processes at an imaging rate of 30-100 ms/frame without disturbing their functions. Here, we report the devices and techniques that realized this performance.